A dipole of magnetic moment `vec(m)=30hatjA m^(2)` is placed along the y-axis in a uniform magnetic field `vec(B)= (2hat i +5hatj)T`. The torque acting on it isA. `-40hatk Nm`B. `-50hatk Nm`C. `-60hatk Nm`D. `-70hatk Nm`

A dipole of magnetic moment `vec(m)=30hatjA m^(2)` is placed along the

1.	A dipole of magnetic moment `vec(m)=30hatjA m^(2)` is placed along the y-axis in a uniform magnetic field `vec(B)= (2hat i +5hatj)T`. The torque acting on it isA. `-40hatk Nm`B. `-50hatk Nm`C. `-60hatk Nm`D. `-70hatk Nm`
Answer» Correct Answer - C `"Here", vec(m)=30hatjAm^(2) and vec(B)=(2hati+5hatj)T` `"Since", vec(tau)=vec(m)xxvec(B)` `=30hatjxx(2hati+5hatj)=60hatjxxhati+150hatjxx 60(-hatk)+150xx0` `=-60hatkNm [therefore hatj xxhatj=-hatkand hatjxxhatj=0]`

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A dipole of magnetic moment `vec(m)=30hatjA m^(2)` is placed along the y-axis in a uniform magnetic field `vec(B)= (2hat i +5hatj)T`. The torque acting on it isA. `-40hatk Nm`B. `-50hatk Nm`C. `-60hatk Nm`D. `-70hatk Nm`

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